Striker fired semiautomatic pistols have a striker assembly positioned within the slide of the pistol. The striker assembly may comprise a striker, a striker spring and a striker bushing. The spring acts between the striker and the bushing to propel the striker against the primer of a chambered cartridge to fire the cartridge when the pistol's trigger is pulled. The spring also serves to bias the bushing against the end cap of the slide. The end cap retains the striker assembly within the slide and is a separate piece which bears against the end of the slide. The end cap is said to “float” between the bushing and the end of the slide. In some pistols it is the biasing force of the compressed spring which maintains the striker assembly positioned within the slide. In other pistols the biasing force is provided by an extractor spring through a transfer bar.
Lightweight prior art pistols which rely on spring biasing to maintain the striker assembly compressed against a floating end cap are at a disadvantage when firing large caliber, powerful rounds. The recoil upon firing may subject the pistol to inertial forces which overcome the biasing force of the striker spring (or the extractor spring) against the end cap. This can cause the end cap to come out of position, which may result in a stoppage of the pistol. It would be advantageous to secure the striker assembly without relying solely on the biasing force of a spring subject to inertial loads.